A number of improvements have been made in the booster seat art in recent years. More recently, improvements and modifications have been made to booster seats and feeding seats with feeding trays which allow a child to enter horizontally rather than vertically. Some of these booster chairs allow for complete removal of the feeding tray, only to reinsert the tray once the child was in their desired position. Other designs hinged the feeding tray with a single swivel only at one end and allow the rotation of the tray such that the child could enter the seating area, and the tray subsequently rotated back to its original position to lock into position and contain the child. These single swivel trays have been temporarily fixed at one end and hinged at the other allowing for little adjustability beyond the ability to rotate the feeding tray about a single axis.
U.S. Pat. No. 4,795,209 (hereinafter Quinlan '209) shows such technology in a portable baby carrier arrangement wherein a feeding tray is adapted to be removably attached at one end and hinged about an axis at the other. The tray opens vertically, that is, up and to the side relative to a seated child, and cannot be adjusted to account for the different size of potential child occupants. A rotating bar defines the rotation axis and also functions as a handle mechanism or as a brace. Importantly, Quinlan '209 can open only along the side opposite to the rotation axis and does not permit the adjustability of a multi-position tray.
Similarly, U.S. Pat. No. 451,058 (hereinafter Koeser '058) discloses a single swivel design that may be rotated along the horizontal or vertical axes only on one side of the chair. The free end of the tray is attachable at the respective opposing arm of the chair, but in no manner does Koeser '058 teach the ability to rotate the tray either vertically or horizontally along that arm to which the free end is attached.
That arrangement is shown in U.S. Pat. No. 113,402 (hereinafter Crandall '402). Crandall '402 discloses a baby carriage in which a barrier is hinged at both ends by a shaft and slot design. A shaft is shown extending upwards from both arms of the carriage and the barrier contains slots or bores configured to receive the vertically extending shafts, such that hinging is not possible when both shafts are engaged in their respective slots. For the barrier to swivel at either end, the barrier must be removed from both shafts, and only one shaft subsequently engaged into its respective slot. The barrier cannot be re-engaged without inserting both shafts into their respective slots either simultaneously or with significant deformation to one of the shafts. Further, Crandall '402 cannot adjust the horizontal placement of the barrier relative to a child occupant of the seat.
A similar design is disclosed in U.S. Pat. No. 1,140,211 (hereinafter Thomas '211) wherein a swing contains a tray pivotably connected at one end and configured to be attached at the other. The removably attached end contains a slot and shaft-like arrangement, but similar to Crandall '402, cannot independently rotate at either end and does not provide adjustability to account for a different sized occupant.
Several prior art patents have disclosed a single-swivel tray adapted to be attached to the arm of a chair, table or other base member. U.S. Pat. No. 5,899,526 discloses a single-swivel tray removably attached to an arm member for the purposes of providing health care. U.S. Pat. No. 5,649,737 discloses a similar single-swivel tray wherein the tray can be detached from a base member by the simple removal of two clips. Further, U.S. Pat. No. 1,324,503 discloses a single-swivel tray which can rotate away from the chair's occupant such that the occupant may place food on the tray and sit in the chair. The tray is subsequently rotated toward the occupant so the food may be accessed in a more comfortable dining fashion. U.S. Pat. No. 686,914 discloses a combination seat wherein single-swivel trays horizontally swing away from one fixed hinge. The seats contain book holders and other scholarly conveniences and are supported by a single post member.